Phylogenomic analysis of the complete sequence of a gastroenteritis-associated cetacean adenovirus (bottlenose dolphin adenovirus 1) reveals a high degree of genetic divergence
Investigation published in Infection Genetics and Evolution
September 1st, 2017
Adenoviruses are common pathogens in vertebrates, infecting a wide range of hosts, but only having rarely been detected and correlated with disease in cetaceans. This article describes the first complete genomic sequence of a cetacean adenovirus, bottlenose dolphin adenovirus 1 (BdAdV-1), detected in captive bottlenose dolphin population (Tursiops truncatus) suffering from self-limiting gastroenteritis. The complete genome sequence of BdAdV-1 was recovered from data generated by high-throughput sequencing and validated by Sanger sequencing. The genome is 34,080bp long and has 220 nucleotides long inverted terminal repeats. A total of 29 coding sequences were identified, 26 of which were functionally annotated. Among the unusual features of this genome is a remarkably long 4380bp E3 ORF1, that displays no sequence homology with the corresponding E3 regions of other adenoviruses. In addition, the fiber protein only has 26% identity with fiber proteins described in other adenoviruses. Three hypothetical proteins were predicted. The phylogenetic analysis indicates that the closest known relative to BdAdV-1 is an adenovirus detected in bottlenose dolphin (KR024710), with an amino acid sequence identity between 36 and 79% depending on the protein. Based on the phylogenic analysis, the BdAdV-1 appears to have co-evolved with its host. The results indicate that BdAdV-1 belongs to the Mastadenovirus genus of the Adenoviridae family, however, it is clearly different from other adenoviruses, especially in the 3`-end of the viral genome. The high degree of sequence divergence suggests that BdAdV-1 should be considered as a novel species in the Mastadenovirus genus. The study also demonstrates the usefulness of high-throughput sequencing to obtain full-length genomes of genetically divergent viruses
Malmberg M., Rubio-Guerri C., Hayer J., Garcia-Parraga D., Nieto-Pelegrin E., Melero M., Alvaro T., Valls M., Sanchez-Vizcaino JM., Belak S. and Granberg F.
| Section of Virology. Department of Biomedical Sciences and Veterinary Public Health. Swedish University of Agricultural Sciences (SLU). | |
| SLU Global Bioinformatics Centre. Department of Animal Breeding and Genetics. Swedish University of Agricultural Sciences (SLU). | |
 | OIE Collaborating Centre Skriv ut - for Biotechnology-based Diagnosis of Infectious Diseases in Veterinary Medicine. National Veterinary Institute (SVA). |
 | Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM). |
| Servicio de Inmunología Viral y Medicina Preventiva (SUAT). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM). |
 | Oceanogràfic. Ciudad de las Artes y las Ciencias. Generalitat Valenciana. |
| Veterinary Services. Avanqua Oceanogràfic. Ciudad de las Artes y las Ciencias. Generalitat Valenciana. |
